A local area network (LAN) as a communication network for a limited area generally includes a cabled LAN and a wireless LAN (WLAN). A WLAN enables communications via a network using radio waves instead of employing a cable. The WLAN has been introduced as an alternative for addressing difficulties in installation, maintenance and movement caused by cabling and become increasingly needed with growing mobile users.
A WLAN is formed of an access point (AP) and a station (STA) as a terminal device. The AP is a device sending radio waves to enable WLAN users within in a coverage area to connect to the Internet and to use the network, which functions like a hub of a cabled network. An AP for a wireless high-speed Internet service provided by an Internet service provider (ISP) is already installed in a service area.
A basic architecture of an IEEE 802.11 network is a basic service set (BSS). The IEEE 802.11 network includes an independent BSS in which terminals in the BSS communicate directly with each other, an infrastructure BSS which involves an AP in communications of a terminal with terminals in and outside the BSS, and an extended service set in which BSSs are connected to extend a service area.